class Solution {
private:
    int nums[26];
public:
    bool checkIfPangram(string sentence) {
        memset(nums, 0, sizeof(nums));
        if(sentence.size() < 26)return false;
        for(int i = 0; i < sentence.size(); i++)nums[sentence[i] - 'a'] ++;
        for(int i = 0; i < 26; i++){
            if(!nums[i])return false;
        }
        return true;
    }
};

//2021.4.18
